Supramolecular Control in Carbohydrate Epimerization: Discovery of a New Anion Host−Guest System
作者:Hai Dong、Martin Rahm、Tore Brinck、Olof Ramström
DOI:10.1021/ja807044p
日期:2008.11.19
A new anion-carbohydrate recognition system is described. Pyranosides with axial protons in 1-, 3-, and 5-position proved efficient, forming relatively strong complexes between the anion and the B-face of the carbohydrate. This system could furthermore be used in supramolecular control in Lattrell-Dax epimerization reactions, leading to either activation or deactivation effects.
Efficient Synthesis of β-<scp>d</scp>-Mannosides and β-<scp>d</scp>-Talosides by Double Parallel or Double Serial Inversion
based on multiple regioselective acylation via the respective stannylene intermediates, followed by inversions to the corresponding manno- and talopyranoside structures by nitrite or acetate substitution. It was found that the ester group was able to induce the inversion of its two neighboring groups in high yields following either a double parallel or a double serial inversion process. By combination
We have developed efficient strategies for the synthesis of glycosyl donors with 2-thioacetyl (SAc) groups in order to synthesize 2-deoxysugars with absolute α/β configuration.